A vacuum cleaner is mainly used for a convenient cleaning at home or office, and there are various kinds of vacuum cleaner.
In general, a vacuum cleaner includes a cleaner main body generating a suction force and filtering alien substances such as dust, crumbs, sand or the like; a cleaner head through which alien substances are sucked together with air by a suction force generated at the cleaner main body; and a connection hose connecting the cleaner main body and the cleaner head.
In such a cleaner, when a suction force is generated in the cleaner main body, alien substances on a floor are sucked together with air through the cleaner head by the suction force and are introduced to the cleaner main body. The alien substances introduced into the cleaner main body together with air are filtered by a filter provided in the cleaner main body, to be collected, and the air is discharged outside.
According to a kind of vacuum cleaner, a collecting filter for collecting alien substances may be installed in the cleaner main body or separately installed at outside.
In such a vacuum cleaner, efficiency of sucking alien substances such as dust, crumbs, sand or the like on a floor together with air and noise generation are affected by a shape of a cleaner head. If a suction path formed between the cleaner head and a floor is big, a suction force for sucking alien substances such as dust is weakened compared to a suction. force generated in the cleaner main body, whereby alien substances are not effectively introduced thereinto. And, if the suction path between the cleaner head and a floor is small, a suction force becomes excessively strong whereby the cleaner head cannot move smoothly and noise is greatly generated.
In addition, a form of the cleaner head used when removing alien substance such as dust, crumbs, sand or the like in a carpet and a form of the cleaner head used when removing alien substances on a non-carpeted floor are difference from each other. Also, there is a cleaner head having one form that can be used in cleaning both carpet and non-carpeted floor.
FIGS. 1, 2 are perspective views showing one embodiment of a conventional cleaner head which is disclosed in U.S. Pat. No. 6,421,875. In the cleaner head, an air channel 12 having a certain width is formed at a bottom edge 11, which comes in contact with a floor, in a longitudinal direction, and a suction hole 13 through which air is sucked is positioned in the middle of the air channel 12. On the basis of the suction hole 12, the air channel on the left side becomes a left air channel, and that on the right. becomes a right air channel. A plurality of air channels 16 is respectively formed at certain intervals therebetween, within a front bottom edge 14 positioned in front of the air channel 12 and within a rear bottom edge 15 positioned in the rear of the air channel 12. Also, a brush 17 may be mounted to the rear bottom edge 15.
When a user cleans a floor, such a cleaner head moves along the floor with the bottom edge 11 contacted with the floor in a state that a suction force is applied to the suction hole 13. External air is sucked into a suction path formed by the air channels 12, 16 formed within the bottom edge 11 and the floor. At this time, the air is sucked to the air channels 16 formed within the front and rear bottom edges 14, 15, generating a vortex. The air is sucked into the suction path, together with alien substances or the like.
However, such a cleaner head is not proper for cleaning a carpet since the cleaner head sucks alien substances only with a suction force of air whereby alien substances such as dust, crumbs, sand or the like positioned between carpet fibers are not removed in cleaning the carpet.
FIG. 3 is a bottom view showing another embodiment of a conventional cleaner head which is disclosed in EP 0,552,652. In the cleaner head, a suction hole 21 having predetermined width and length is formed in a bottom of the head which comes in contact with a floor, and a front suction channel 21 and a rear suction channel 23 having certain width and length are formed in its bottom. The front suction channel 22 and the rear suction channel 23 are formed in a rectangular shape, and side passages 25, 26 are respectively formed at both walls of the two channels 22, 23.
The suction holes 21 are formed in the middle of the suction channel 22 and of the rear suction channel 23. A brush strip 26 is positioned between the first suction channel 22 and the rear suction channel 23. An end of the brush strip 26 is formed in a concavo-convex form, and its height is almost the same as a height of the bottom part of the head.
When a user cleans a floor or a carpet, such a cleaner head moves along a floor with a bottom of the head contacted with the floor in a state that a suction force is applied to the suction hole 21. External air is introduced thereinto through suction paths respectively formed by the front suction channel 22 of the cleaner head and a floor and by the rear suction channel 23 and the floor, and herein, the air is introduced, together with alien substances. At this time, the external air is introduced into the suction path through the side passages 24, 25, and the brush strip 26 scrapes carpet fibers.
However, in such a cleaner head, pressure is leaked between the front suction channel 22 and the rear suction channel 23 because of a brush strip 26 positioned between the front suction channel 22 and the rear suction channel 23 and having a concavo-convex form, thereby deteriorating intensity of flow. In addition, the brush cannot sufficiently scrapes carpet fibers to their root portions since the height of the brush-strip 26 is the same as that of the bottom part of the head, and air is sucked from the side, thereby cleaning cannot be sufficiently performed.
FIGS. 4, 5 are views showing still another embodiment of a conventional cleaner head, which is disclosed in EP 0,885,586. In the cleaner head, a suction channel is formed in a bottom edge 31 which comes in contact with a floor, and a suction hole 32 is positioned in the middle of the suction channel. A scraper blade 33 made of an elastic material and having certain width and area is mounted in front of the bottom edge 31, and a brush bar 34 is mounted in the rear of the scraper blade 33. When viewed based on the floor, an end of the scraper blade 33 is higher than the bottom edge, and an end of the brush bar 34 is higher than that of the scraper blade 33. A plurality of holes 35 is formed within the scraper blade 33 at certain intervals therebetween, and notches 36 corresponding to positions of the holes 35 are formed within the end portion of the brush bar 34.
When a user cleans a carpet or a non-carpeted floor, such a cleaner head moves along the floor with the bottom edge 31 contacted with the floor in a state that a suction force is applied to the suction hole 32. External air is sucked thereinto through a suction path formed by the suction channel and the floor, and herein, the air is sucked, together with alien substances. At this time, external air is sucked thereinto through both sides and a rear side of the bottom edge 31.
The scraper blade 33 and the brush bar 34 positioned in front of the bottom edge 31 push back carpet fibers.
However, in such a cleaner head, the scraper blade 33 and the brush bar 34 push back carpet fibers from outside the suction path, that is, in front of the bottom edge 31 and external air is sucked through a suction formed at both sides and a rear of the bottom edge 31, whereby alien substances cannot be effectively sucked from the roots of carpet fibers.
By the above mentioned conventional arts, when cleaning a non-carpeted floor, alien substances are sucked in a certain amount by a suction force applied to a suction path formed by an air channel and a floor, whereas when cleaning a carpet, alien substances cannot effectively sucked from roots of carpet fibers. Especially, if the carpet fiber is long, alien substances such as dust, crumbs, sand or the like are not sufficiently sucked from a root of the carpet fiber.
In addition, in the cleaner heads, a suction path through which alien substances are sucked is formed at both sides of the head when viewed in a direction that a cleaning proceeds, whereby alien substances are not effectively sucked.